Adapter for interconnecting optical fiber connectors or the like

Abstract: An adapter assembly (10) is provided for interconnecting a pair of opposing optical fiber connectors generally along an optical axis (12). The adapter assembly is constructed as a double-ended receptacle for receiving the connectors in opposite open ends (18, 20) thereof. The assembly further includes a pair of halves (14, 16) each defining one of the open ends for receiving one of the connectors. Each half has an interconnection (22, 32) operatively associated with its respective connector. At least one latch arm (40) is provided on one of the adapter halves, within the peripheral bounds thereof, projecting generally parallel to the optical axis (12) toward the other adapter half and engageable with a complementary latch (42a) on the other half.

Description: Field of the Invention This invention generally relates to the art of connecting devices and, particularly, to an adapter for interconnecting a pair of opposing optical fiber connectors such as SC-type connectors. Background of the Invention Optical fibers are used for high speed communications and data transmissions. Optical fiber connectors are used on opposing fiber ends to provide means for readily coupling and uncoupling the fiber ends in a quick-release fashion. Rather than providing male (plug) and female (receptacle) connectors as is prevalent in the electrical connector art, optical fiber connectors often are interconnected by adapters which not only interconnect a pair of opposing optical fiber connectors, but the adapters facilitate aligning the optical fibers to prevent transmission losses at any given interconnecting interface. One type of optical fiber connector design commonly is identified as an "ST" connector ("ST" being a trademark of American Telephone and Telegraph Co.). Such connectors generally are of a bayonet-type interconnection. Basically, this type of connection includes a plug-type coupling having one or more outwardly projecting lugs, along with a relatively rotatable socket-type coupling having a spiral or L-shaped slot for respectively receiving each of the lugs. When an adapter is used, the bayonet-type plug couplings or connectors are terminated to opposing optical fiber ends, and the adapter has opposite receptacle ends provided with lug-receiving slots for receiving the opposing optical fiber couplings or connectors. Another type of optical fiber connector design commonly is identified as an "SC" connector, first manufactured by Nippon Telegraph and Telephone Co. of Japan. Generally, this type of interconnection is based on a push-pull concept. Again, plug-type couplings or connectors are terminated to opposing optical fiber ends. When an adapter is used, it again is designed as a double-ended receptacle for receiving the opposing optical fiber connectors, but in a push-pull fashion. The connectors and the adapter have complementary interengaging latch means, such as hooked latch arms for engaging latch bosses, to interconnect the adapter and the connectors. One of the problems with adapter designs heretofore available, whether used with ST, SC or other fiber optic connectors, is that the adapters are fabricated with two interconnected halves. Each half defines one receptacle end of the adapter for receiving a respective one of the opposing optical fiber connectors. Consequently, some form of means must be provided for joining or interconnecting the adapter halves. Most often, the adapter halves are provided with radially outwardly extending flanges which are abuttingly engaged, and fasteners (such as rivets) are used to rigidly join the flanges outside the bounds of the adapter body defined by the two halves thereof. Such flanges take up valuable "real estate" in compact or tight interconnection environments, and the use of such fasteners as rivets require additional and expensive manufacturing steps. In addition, such means for joining the adapter halves are not easy to assemble in the field. JP-A-03 121 403 discloses an optical connector adapter for interconnecting a pair of opposing optical fiber connectors along an optical axis, wherein the adapter is constructed as a double-ended receptacle for receiving the connectors in opposite ends thereof and which includes an outer peripheral wall of molded plastic material, the adapter further comprises interconnecting means operatively associated with its respective connector. Another problem with such adapters is that they often are used in conjunction with a panel. FR-A-2 512 218 describes an optical fibre connector providing two latch arms engageable with a respective leg of an U-shaped support in order to mount the adapter thereon. Document US-A-4,240,695 discloses a connector for optical fibers wherein the connector body is assembled from two mating sections having horizontal and vertical mounting flanges designed as a kind of sliding guide and which can be clamped in between two nuts of a bolt to attach the optical fiber connector on a support means such as a panel. An adapter however may be also located in an aperture in a panel, and a pair of opposing optical fiber connectors thereby can be interconnected from opposite sides of the panel into the mounted adapter. Heretofore, separate mounting means, such as metal clips, have been used on adapters to mount the adapters in a panel. Again, such separate components are not cost effective and are not favorable in field use. This invention is directed to solving the problems encountered with adapters of the character described above, particularly those problems identified above, and to satisfy a need for a simple, cost-effective and easy to use adapter design. Summary of the Invention An object, therefore, of the invention is to provide a new and improved adapter for interconnecting a pair of opposing optical fiber connectors as defined in claim 1. In the exemplary embodiment of the invention, the adapter is constructed as a double-ended receptacle for receiving the connectors, generally along an optical axis, in opposite open ends of the adapter. It further comprises interconnecting means operatively associated with its respective connector and an outer peripheral wall of molded plastic material. A deformable rib projects outwardly of the outer wall and is engageable with an inner peripheral edge of an aperture in a panel and provides the sole means for mounting the adapter in the panel aperture. The deformable rib is elongated and extends axially of the adapter. Still further, the deformable rib has a dove-tail cross-section to provide acute corners which are readily deformable. The adapter further includes a pair of halves each defining one of the open ends for receiving one of the connectors. Each half has interconnecting means associated with its respective connector. The invention contemplates that complementary interengaging latch means be provided between the adapter halves in the form of at least one latch arm on one of the adapter halves projecting generally parallel to the optical axis toward the other adapter half and engageable with a complementary latch on the other half. As disclosed herein, the latch arm on the one adapter half has a hooked latch portion for interengaging a latch shoulder on the other adapter half. The halves are molded of dielectric material, such as plastic or the like, and the latch arm, thereby, is resilient to snappingly engage the latch shoulder. In the preferred embodiment of the invention, the latch arm is located at an outer peripheral face of the one adapter half. Preferably, the latch arm is located within the transverse bounds of the outer peripheral face of the one adapter half. Still further, the latch arm preferably has an outer peripheral face generally flush with the outer peripheral face of the one adapter half. The latch arm is insertable in a recessed area in an outer peripheral face of the other adapter half, and the complementary latch on the other adapter half is located in the recessed area. As disclosed herein, the adapter halves each have one of the latch arms engageable with a complementary latch on the other half. When assembled, one latch arm and its respective latch are located on each of a pair of opposite sides of the adapter. Other objects, features and advantages of the invention will be apparent from the following detailed description taken in connection with the accompanying drawings. Brief Description of the Drawings The features of this invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with its objects and the advantages thereof, may be best understood by reference to the following description taken in conjunction with the accompanying drawings, in which like reference numerals identify like elements in the figures and in which: FIGURE 1 is an exploded perspective view of the adapter assembly of the invention; FIGURE 2 is an end elevational view of the adapter assembly; and FIGURE 3 is a partial vertical section taken generally along line 3-3 of Figure 2. Detailed Description of the Preferred Embodiment Referring to the drawings in greater detail, the invention is embodied in an adapter assembly, generally designated 10, for interconnecting a pair of opposing optical fiber connectors generally along an optical axis 12. The interconnectable optical fiber connectors are not shown, but it should be understood that such connectors are well known in the art and are commonly identified as "SC" connectors as fully described in the "Background", above. Generally, the adapter assembly is constructed as a double-ended receptacle for receiving the connectors in opposite open ends thereof. The adapter assembly includes a pair of adapter halves, generally designated 14 and 16, each defining one of the open ends for receiving one of the optical fiber connectors. More particularly, adapter half 14 includes an open end 18 for receiving one of the pair of opposing optical fiber connectors, and adapter half 16 has an open end 20 for receiving the other of the pair of opposing optical fiber connectors. In essence, the open ends define receptacles for the plug-type connectors in a push-pull fashion. Each adapter half 14 and 16 mounts an insert, generally designated 22, therewithin. The inserts are substantially identically constructed. In other words, if the right-hand insert 22 shown in Figure 1 for adapter half 16 is turned 180° relative to axis 12, it would be substantially identical in construction and orientation to that depicted by insert 22 for adapter half 14. Therefore, only one of the inserts will be described below. Each insert 22 includes an inner plate portion 24 for abutting the plate portion of the other insert when in assembled condition as shown in Figure 3. Lugs 26 project from plates 24 to overlie the edges of the plate of the opposite insert to facilitate axially aligning the inserts. In addition, the left-hand insert is assembled into adapter half 14 in the direction of arrow "A" (Fig. 1), and the right-hand insert is assembled into adapter half 16 in the direction of arrow "B". Lugs 26 abut against interior shoulder means 28 (see adapter half 16 in Fig. 1) to rigidly lock the inserts in abutting relationship within the adapter halves when in fully assembled condition as shown in Figure 3. Inserts 22 are unitarily molded of dielectric material such as plastic or the like, and each insert includes a pair of connecting arms 30 projecting axially toward the respective end of its adapter half. Connecting arms 30 include hook portions 30a for interconnection with appropriate latch means on the optical fiber connectors as is known in the art with push-pull SC connectors. Each insert further includes an integral, axially outwardly directed cylindrical boss portion 32 for receiving one end of a sleeve 34. In other words, sleeve 34 spans both inserts within cylindrical boss portions 32 as seen in Figure 3. The sleeve is effective to axially align the fiber ferrules of the opposing optical fiber connectors. Except for the panel-mounting means which will be described hereinafter, adapter halves 14 and 16 are of substantially identical construction and function, except for their 180° opposite orientation in assembly as shown in the drawings. Therefore, adapter half 16 will be described in detail, below, with the suffix "a" being used in conjunction with the reference numeral 14 to indicate identical corresponding components of adapter half 14. More particularly, adapter half 16 includes a top wall 16a, a bottom wall 16b, a side wall 16c and an opposite side wall 16d which combine to provide a rectangular configuration defining open-ended receptacle 20 (Fig. 3). Each adapter half is unitarily molded of dielectric material, such as plastic or the like, and shoulders 28 (Fig. 1) are molded integrally with side walls 16c and 16d for abutting inserts 22. An alignment pin 36 projects inwardly of the inner edge of side wall 16d and a complementary mating alignment hole 38 is formed in the inner edge of opposite side wall 16c for interengagement with an identical alignment pin and hole of side walls 14c and 14d of adapter half 14. The invention contemplates a unique complementary interengaging latch means between adapter halves 14 and 16 to eliminate any projections extending outwardly from the adapter assembly, such as the attachment flanges of the prior art. More particularly, a flexible latch arm 40 projects axially inwardly from the edge of each side wall of each adapter half 14 and 16. In essence, the side walls of the adapter halves define outer peripheral faces, and it can be seen clearly in Figure 1 that the outsides or outer peripheral faces of the latch arms are flush with the outer peripheral faces of the side walls of the adapter halves. In fact, looking at the end view of Figure 2, the latch arms cannot even be seen. Therefore, the latch arms are contained entirely within the transverse bounds of the adapter assembly and do not project outwardly therefrom. Each adapter half has a complementary recessed area 42 to accommodate a respective one of the latch arms 40 and, thereby, maintain the latch arms within the peripheral bounds of the adapter. The outer distal ends of the latch arms are provided with chamfered latch hooks 40a, and each recessed area 42 is provided with a complementary latch shoulder 42a for snappingly receiving hooks 40a. In assembly, when adapter halves 14 and 16, along with their respective inserts 22 and sleeve 34, are assembled from the condition shown in Figure 1 to the assembled condition shown in Figure 3, latch arms 40a of each adapter half enters a respective one of the recessed areas 42 of the other adapter half. Chamfered latch hooks 40a resiliently bias the latch arms radially outwardly until the hooks snap back inwardly into engagement with latch shoulders 42a. Lastly, Figure 3 shows adapter assembly 10 mounted in an aperture 50 in a panel 52. Adapter half 14 includes a transverse lip 54 for abutting against one side of panel 52 to define a mounted position of adapter assembly 10. The invention contemplates a feature for eliminating the extraneous panel mounting clips of the prior art. Specifically, an axially extending, integrally molded rib 56 projects from the bottom of adapter half 14. As seen in Figure 3, an aligned extended portion 56a of the rib also is provided on the bottom of adapter half 16. Referring back to Figure 2, rib 56 can be seen to be dovetailed in configuration to define acutely pointed corners 56b. With the adapter halves being molded of plastic material, these acute or pointed corners are readily deformable upon insertion into an appropriately dimensioned panel aperture to provide an interference fit and, thereby, secure the adapter assembly within the panel aperture without the use of any extraneous mounting clips or other hardware. It will be understood that the invention may be embodied in other specific forms without departing from the scope thereof. The present examples and embodiments, therefore, are to be considered in all respects as illustrative and not restrictive.

Claims: An adapter assembly (10) for interconnecting a pair of opposing optical fiber connectors generally along a fibre axis (12), the adapter assembly comprising : a double-ended receptacle for receiving the connectors in opposite open ends (18, 20) thereof, the receptacle being formed by a pair of halves (14,16), each half defining one of said open ends for receiving one of the connectors, and each half having interconnecting means (22, 32) operatively associated with its respective connector, complementary interengaging latch means (40, 40a, 42a) between the receptacle halves in the form of at least one latch arm (40) on one of the receptacle halves projecting generally parallel to said axis toward the other receptacle half and engageable with a complementary latch (42a) on the other half, characterized in that at least one of the receptacle halves includes on an outer peripheral face a deformable rib (56) parallel to said optical axis and engageable with an inner peripheral edge of an aperture in a panel (52) and providing the sole means for mounting the adapter in the aperture in the panel, wherein said deformable rib (56) has a dove-tailed configuration to provide acute corners (56b) parallel to said optical axis and which are readily deformable upon insertion to provide an interference fit so as to secure the adapter assembly within the panel aperture, and at least one of the adapter halves includes on an outer peripheral face opposed to the face holding the deformable rib a tranverse lip (54) for abutting against one side of the panel (52) to define a mounted position of the adapter assembly (10), as said panel. The adapter assembly as set forth in claim 1, wherein said latch arm (40) on the one adapter half has a hooked latch portion (40a) for interengagement with a latch shoulder (42a) on the other adapter half. The adapter assembly as set forth in claim 1 or 2 , wherein said latch arm (40) is located at an outer peripheral face (14c, 14d, 16c 16d) of the one adapter half different those faces holding said deformable rib (56) and said transverse lip (54). The adapter assembly as set forth in claim 3 , wherein said latch arm (40) is located within the transverse bounds of said outer peripheral face (14c, 14d, 16, 16d) and does not project outwardly therefrom. The adapter assembly as set forth in claim 4 , wherein said latch arm (40) has an outer peripheral face generally flush with the outer peripheral face of the one adapter half. The adapter assembly as set forth in any of claims 1 to 5 , wherein said latch arm is insertable in a recessed area (42) in an outer peripheral face of the other adapter half. The adapter assembly as set forth in any of claims 1 to 6 , wherein said complementary latch (40) on the other adapter half is located in said recessed area (42). The adapter assembly as set forth in any of claims 1 to 7 , wherein the adapter halves and their respective interconnecting means are of molded plastic material. The adapter (10) assembly as set forth in any of claims 1 to 8 , including an outer peripheral wall (14b) of molded plastic material, wherein the integral deformable rib (56) is projecting outwardly of said outer wall (14b). The adapter as set forth in any of claims 1 to 9 , wherein said deformable rib (56) has an elongated shape and extends parallel to the axis of the adapter.

Inventors: BELENKIY YURIY, GROIS IGOR, MAKHLIN ILYA, BELENKIY, YURIY, GROIS, IGOR, MAKHLIN, ILYA
Applicants: MOLEX INC, MOLEX INCORPORATED
Application year: 1994
Main classification: G02B6
IPC codes: G02B6